Movable electric conductor and clamp



Se t. 10, 1929. c. s. DAVIS 1727,814 I MOVABLE ELECTRIC CONDUCTOR AND CLAMP Filed Feb. 20. 1928 [N VENTOR [k /k; J. Jan's w A TTORNEY Patented Sept. 1Q, 1929.

' UNITED STATES PATENT ()FFlCE.

CHARLES S. DAVIS, OF PASCO, WASHINGTON, ASSIG-NOR OF ONE-THIRD TO R. P. ST/VANNEB, OF PASCO, WASHINGTON, AND ONE-TH1RD T0 C. THOMAS IVIYEBS, OF

YAKIMA, WASHINGTON.

MOVABLE ELECTRIC COIIDUCTOR AND CLAMP.

Application filed February 20, 1928.

This invention relates to movable electric conductors and clamps and has as one of its objects to provide a device that is adapted to be secured to a smooth part, such as glass, and that will provide an electric binding post that will remain stationary on said smooth part, and that will provide an electric conductor that may be rotatable in the clamp and also project through the smooth part to which it is secured, and, when the conductor is rotatable utilizing the securing means as a turning knob.

Another object of the invention is to provide a movable electric conductor and clamp adapted for use on the face of instruments having indicating hands to provide for closing a circuit through the hand and electric conductor, to conduct an electric current to the exterior of said instrument.

With these and other objects in view ref erence is now had to the accompanying drawings in which Fig. 1 is a front elevation of a typical instrument showing the application of the device;

Fig. 2 is a side elevation of a similar instrument showing the device installed, with part of the instrument broken away to better show its application; a

Fig. 3 is a sectional elevation of the device assembled; and

Fig. 4 is a sectional elevation of the device disassembled.

Having reference to the drawings like numerals refer to like parts throughout the several views and the numeral 1 refers to an instrument which may represent one of many classes of instruments, as a thermometer, and the numeral 2 represents the device as a whole. As above mentioned the instrument is typical and in this case consists of a case 3 which houses the working parts (not shown) and in which: is contained a dial 4, an indicating hand 5 mount-ed on a shaft 6, and provided on its face with a glass cover 7 secured in the case in the usual manner of instrument construction.

In the following description the glass cover will be termed the smooth part to inelial NO. 255,610.

dicate an object having smooth surfaces to which the device may be clamped.

The device comprises a post 8, preferably of the shape of a frustrum'of a cone, with its base 9 of relatively lar e size to provide and present a frictional bearing adapted to engage one side of the smooth part 7 with sufficient friction to maintain its position un der working conditions.

Attached to or formed integral with the post 8 is a binding post 10 which may be of any appropriate design to receive the wire 11 secured by means of a screw 12, of a circuit (not shown), and from this inclusion the post as a Whole may be properly termed a binding post.

The opposite end of the post will be termed the outer friction bearing 13 and extending from this end downward in the post to nearly the base 9 is a recess 14, which houses a coiled spring 15 constructed slightly longer than the depth of the recess whereby to provide for a predetermined tension on the parts of the device in a manner and for a purpose to be explained.

In the remaining portion of the post between the bottom of the recess and the base a bearing orifice 16 is provided and this orilice is of smaller diameter than the recess to leave a shoulder 17 against which one end of the spring 15 will bear in its efforts to press the base against the smooth part.

This orifice, as its name implies, forms a bearing and rotatably mounted in this bearing is a bolt 18 that is projected through the smooth part, it being drilled for the purpose, and on through the recess 14 and spring 15 finally to project beyond the outer friction bearing 13.

The bolt is provided on its inner end with a head 19 whose base 20 now providing a relatively small friction surface which, owing to the relative sizes of this base and the base 9 of the post, obviously will nor mally aiford less resistance against the op posite side of the smooth part from the base.

The head is adapted to receive a conductor wire 21 by being pressed and soldered into the slot of the head, in the usual manner of such construction.

The outer end of the bolt 18 is threaded and a tension nut 22 threadedly engages the threaded end of the bolt and, when screwed down against the outer friction bearing 13 compresses the spring 16 to the depth of the recess and simultaneously maintains the unequal frictional resistance between the two surfaces.

By this arrangement it will be noted that the spring will provide a certain fixed tension only as it bears against the tension nut of the bolt and the shoulder 17 in the post, and that this tension will influence the bolt to positively remain in the position to which it is rotated, thus preventing accidental displacement of the conductor wire When the device is set for operation.

It will further be noted that by tightenin the tension nut the relatively large base wil offer greater frictional resistance to turning; on the smooth part, and that the same true of the base 20 of the bolt head, however, regardless of how tight the base of the post and the base of the head the bolt are drawn together the enlarged base of the post will offer the greater resistance to turning, owing to its relative size, than the bolt, and hence the post will remain stationary during the rotative movement of the bolt.

To rotate the bolt a turning knob 28 is provided and this knob is constructed circular in form for convenience of operation and threadedly engages the bolt to act as a locknut to secure the tension nut against loosening on the bolt from jar or other causes.

Obviously friction washers, such a bas Washer 24, a head washer 25, and an oute. friction bearing washer 26 may be user placed between the parts as shown wherewith to increase the friction without applying a tension on the bolt that might brea t. smooth part under sudden changes or tea" perature, or under too great a strain generally.

In use, and for assembling, a hole is drilled in the glass cover of the instrument and the bolt is then passed through this hole, and the post and spring are mounted on the bolt, (together with the respective washers, if used) and the whole secured to the smooth part by the tension nut and the turning knob.

The Wiring is now completed to the bind ing post 10 when the device is ready for operation.

The conductor wire is then moved to the desired position by the turning knob and When contact is made between the rest of the circuit, the circuit will be completed between the binding post 10 and the conductor Wire 21 the flow of electricity passing through the binding post and the post 8, through the bolt 18 which contacts the post 8 in the bearing orifice 16, through the bolt to the head 19, and thence to the conductor wire 21.

Having thus described my invention, I claim 1. A movable electric conductor and clamp, adapted for securcment to a smooth part, and comprising a binding post, having a base adapted to provide a relatively large frictional surface for engagement with one side of said part, and a movable conductor rotatably secured in said smooth part and said post, and means to secure and prevent the rotation of said post.

2. A. movable electric conductor and clamp, adapted for securcment to a smooth part, and comprising a binding po t, having a base adapted to present a relati ely large frictional surface to one side of id part, and movable conductor rotatably secured in said smooth part and said post, and means to secure and prevent rotation of said post and permit the rotation of said conductor.

3. A movable electric conductor and clamp, adap .cfor securement to a smooth part, and comprising a binding post having a relatively large frictional base adapted to engage one side of said part, and pro vided with a recess, a yield ng; means mounted in said recess, a movable conductor secured in said smooth part and in said post, pr 7 cted through. said yielding means to obtain tension therefrom, and provided with means to secure and prevent the rotation of said post and permit the rotation of said conductor. w

A .ovable electric conductor and clamp, adapted for securcment to a smooth part, and comprising a post, having an enlarged friction producing base adapted to engage one side of said part, and adapted to form a binding post, a bolt rotatably mounted in said part and in said post, and adapted to provide a movable conductor therethrough, said bolt having a head adapted to receive a conductor wire, and provided with a friction surface of less re sistance than the said base, and means to simultaneously and yieldingly maintain the unequal frictional resistance between the two surfaces.

5. A movable electric conductor and clamp, adapted for securcment to a smooth part, and comprising a post, having an offset forming a binding post, and provided with a frictional bearing adapted to engage one side of said part, and having a recess, a yielding means mounted in said recess, a bolt rotatably mounted in said part and in said post, to provide a movable conductor therethrough, said bolt having a head adapted to receive a conductor wire, and provided with a friction surface ofless rez- *i'ance than the said base, and adapted to engage the opposite side of said parts,

means to provide a fixed tension influenced by said yielding means to said bolt and post, said means forming a securing nieans therefor.

6. A movable electric conductor and clamp, adapted for securenient to a smooth part, and comprising a post, having a binding, post formed integral therewith, and provided with a relatively lar 'e frictional bearing, adapted to engage one side of said part and containing a yielding means, a bolt passed through said part and through said post for rotation therein under tension of said yielding means, and to form a conductor therethrough, and provided with a relatively small frictional surface positioned opposite to that of the said frictional bearing, and adapted to afford less resistance than that of said base, means to secure said bolt in said part and said post, said means being disposed to regulate the frictional resistance of the bolt and post against the part without effecting the tension of the yielding means, said means forming an operating knob.

7. A movable electric conductor and clamp, adapted for securenient to smooth part, and conigrising recessed post, having an enlarged friction base, an offset portion formed integral therewith and providing a binning post, a friction washer interposed between said base and one side of the smooth part, a head washer positioned on the opposite side of the smooth part to be clamped, a bolt adapted to form an electrical continuation of said post and to secure t 1e "riction washers in frictional contact with "he sniooth part, a spring mounted in said ecessed portion of said post, outer fricion bearing washer mounted on said bolt or frictional contact with the outer nd of "aid post; a tension nut threadedly I said bolt and adapted to coin said spring, and a loclznut positioned in looking relation to said tension nut and adapted to forin a turning knob.

In testimony whereof I afar; 111V signature,

CHARLES 

